Nylon should be avoided at all cost for applications that are wetted
with water !!!!!!!!
Nylon quickly hydrolyzes (rapid breaking down of the long chain
macromolecules ... analagous to rust (intergrannular corrosion) in
metals); and, rapidly loses material strength. Nylon6 (most common)
is the absolute worst and Nylon66 is close. In industry, the
hydrolysis is usually found after a few months in water wetted
application.

Marelon, etc. is at least stabilized by inhibiters, etc. to better
withstand this hydrolysis.